Primary Outcome Measures:
- Relapse rate over 24 months. [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]
Secondary Outcome Measures:
- Proportion of patients in sustained remission (i.e. remission at 3 months sustained for 6 months and remission at 6 months sustained for a further 12 months); [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]
- Time to remission; [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]
- The average steroid dosage at 6 months, 1 year, 18 months and 2 years in abatacept and placebo groups respectively; [ Time Frame: 2 years ] [ Designated as safety issue: No ]
- Time to ANCA negativity by immunofluorescence or negative anti-PR3 or anti-MPO Ab test by ELISA. [ Time Frame: 2 years ] [ Designated as safety issue: No ]
- Proportion of patients defaulting to cyclophosphamide (MMF, azathioprine or other rescue) therapy. [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]
- Proportion of patients unable to stick with trial protocol. [ Time Frame: 2 years ] [ Designated as safety issue: No ]
- Degree of chronic disease activity [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]
- Health related quality of life [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]
The drugs that are normally used to treat patients with AAV are quite effective, but up to 20% of patients relapse within 18 months. The drugs used can also have significant side effects. Abatacept, also known as CTLA4Ig, acts by blocking vital costimulatory signals required for T lymphocytes to be activated. As ANCA associated vasculitis is believed to be an autoimmune condition and dependent on autoreactive T cells, there is some reason to believe this drug would be effective. Abatacept has already received a license by the FDA for use in Rheumatoid arthritis where it has proven to be effective even in patients unresponsive to Etanercept (TNF blockade).
120 patients with AAV will be invited to take part in this study, from hospitals in the UK and Europe. The patients will receive standard therapy with methotrexate and steroids as well as 12 months of abatacept or placebo. They will be followed for a further 12 months.
The primary objective of this study is to assess the relapse rate over 24 months, in patients with acute AAV, presenting at first diagnosis or relapse, in the two arms of the study.